ENTOMOLOGIST AND BOTANIST. 



195 



Although the complete history of the Gordius 

 remains unUnown, it is nevertheless clearly 

 ustablishod that it passes a jrreat part of its ex- 

 istence as a piirasite in various species of insects. 

 I have uevei' had tlie good fortune to observe 

 any of our sprcies actually wilhin, or proceeding 

 from, insecls, though I have, iu a multitude of 

 instances, seen the allied genus, Mermis, or 

 AVhiie Hair-worm, within insects. A single 

 si)ecinieu, from which I tiist described the Ro- 

 bust Gordius, was sent (o me, together with a 

 Grasshopper {Orchelimum gnicile), which was 

 said to have contained the worm. 



The common European species {(iordius 

 aquaticHS, etc.) have been frequently observed 

 within and proceeding from insects, which are 

 there viewed as their natural habitation for the 

 time, as much so as is the water subsequently. 

 The names of various Beetles, especially the 

 Ground-beetles, and also Grasshoppers, are 

 given, which are infested with Gordii. 



I have observed a White Hair-worm {Mermis) 

 proceeding from the Carolina Grasshopper 

 {(Edipoda Carolina, Linn.), whilst the latter 

 was struggling in a ditch into which it had 

 jumped from being alarmed. Perhaps in this 

 way we may account for the occasional appear- 

 ance of a Gordius in a drinking trough, or a 

 puddle on the road. 



A brief notice of the structure of the Gordius 

 may not be uninteresting in connectiou with the 

 history of the animal. Notwithstanding the 

 simplicity of its outward form, its organization 

 is ot complex character, and certain of its pecu- 

 liarities are of special Interest to the physiolo- 

 gist. 



Though the Gordius has had the reputation 

 of being able to bite, I must confess that I have 

 not been able to satisfy myself that the animal 

 actually possesses a mouth. For jaws I suspect 

 the foi-ks of the tail of the male have been mis- 

 taken. Some European observers have failed 

 to detect the mouth, though Dr. George 

 Meissner, of Gijttingeu, a most accurate in- 

 vcsiigalor, both describes and figures it. 

 Sometimes, and indeed generally, I have de- 

 tected the appearance of a minute orifice, or 

 pore, to one side of the summit of the head in 

 the Variable Gordius, but iu other instances and 

 in other species, including the large Robust 

 Gordius of Kansas, I could distinguish nothing 

 of the kind, the head end appearing as smooth 

 as a watch crystal, without the slightest sign of 

 even a depression. 



All reliable investigations, in addition to my 

 own examinations, prove the total absence of 

 anything like a stomach, intestinal canal and 



vent in Gordius. The interior of the body is 

 occupied by a soft, white matter, reminding oue 

 of the pith of sassafras or other plant. This 

 matter consists of polyhedral cells, resembling 

 vegetable cellular tissue, and formsacontiiuious 

 mass from one end of the body to the other. 

 Spaces included in this cellular tissue are occu- 

 pied by the genital and other organs. According 

 to Dr. Meissner, the mouth opens into a short 

 gullet which expands upon the upper end of the 

 mass of cellular tissue. 



Nutritive liquid matter imbibed by the mouth, 

 or the thin investment of the head end of the 

 animal, it is evident, can only pass throughout 

 the body of the latter by endosmosis from cell 

 to cell of the interior cellular structure. The 

 arrangement of the latter, and the transmission 

 of nutritive liquid, reminds one of the organiza- 

 tion and passage of liquids through the lootlets 

 of a plant. 



Nothing like a system of blood-vessels, or 

 nutritive tubes, nor like the tracheal air-vessels 

 of insects, can be detected in the structure of 

 the worm. 



Whilst parasitic in insects, the Gordius is 

 bathed in a rich and highly aerated nutritive 

 material, and would thus not appear to require 

 either an apparatus for the ingestion of food 

 nor one for respiration. Perhaps, too, on 

 account of the absence of a digestive and res- 

 piratory apparatus, when the Gordius first 

 escapes from its abundant provision of "aerated 

 bread," it is stimulated to incessant activity in 

 the water to fulfill at least its respiratory need. 



The generative apparatus of the female con- 

 sists ot a pair of ovaries, contained in the in- 

 terior cellular tissue of the body, extending the 

 greater part of the length of the latter on each 

 side, and conjoining in a common receptacle 

 below, which terminates at the genital pore. In 

 the male the testes hold a similar relatiojiship, 

 and terminate in like manner. 



Of other interior organs, there is a tubular 

 gland extending through the axis of the body, 

 and a cylindrical cord, apparently muscular, 

 extending along the ventral side. 



The nervous system consists mainly of a cord, 

 without distinct or separate ganglia, extending 

 along the ventral side, between the muscular 

 cord just indicated and the general envelope of 

 the body. In the head the nervous cord divides 

 on each side of the muscular cord, aud, accord- 

 ing to Dr. Meissner, becomes continuous with 

 a ring surrounding the gullet. No eyes or other 

 organs of special sense appear to exist 



The external integument of the body consists 

 of a thin cuticle of pavement-like cells, and a 



